Amplitude Fluctuations of Sound Transmitted in the Surface Duct.
Abstract
A short field experiment was done to determine the fluctuation of sound propagating in and below the surface duct. Short pulses at an ultrasonic frequency and cw sound at 1120 Hz, were transmitted to distances between two and ten miles. The received signals were found to be Rayleigh-distributed below the duct at both frequencies. Within the duct, the Rayleigh distribution was also found at the higher frequency, but not at the lower. The results verify the view that reflection and scattering from the rough moving sea surface is the dominant cause of amplitude fluctuation in surface-ducted propagation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 26, 1974
- Accession Number
- AD0786728
Entities
People
- R. J. Urick
Organizations
- Naval Ordnance Laboratory